Obs. : 2010-10-09 Planet Ly alpha (photons/cm^2/sec) Mercury 3.783e+11 Venus 3.942e+11 Earth 3.708e+11 Mars 3.970e+11 Jupiter 3.708e+11 Saturn 3.783e+11 Uranus 3.708e+11 Neptune 3.787e+11 Pluto 3.951e+11